There a lot of stories about dooms day. I invite you all to put forward your ideas according to you that will contribute in finishing the earth. 1. I don't think that there will be a nuclear holocaust. We are not insane enough. 2. I don't think there will be an epidemic spread. Science is too advance. I think natural calamity could be a cause. I think people will become homosexual and will not give birth to children It could be a serious cause and threat.